Heads up, people—I know you've cut out pizza, cake, alcohol, bacon, pancakes, raw cookie dough, and whole sticks of butter rolled in Pop Rocks, and your only source of pleasure these days is a nice, long sleep-in on Saturday mornings, but STOP IT. Sleeping in is making you fat too.

At least that's what a German sleep study suggests. They studied the sleeping habits of 65,000 participants and discovered that those with drastic differences between their weekday and weekend sleep patterns were more than three times likely to be obese.

The researchers dubbed these patterns "social jet lag":

Social jet lag is "the discrepancy between what our body clock wants us to do and what our social clock wants us to do," says Till Roenneberg, Ph.D., a professor at the University of Munich's Institute of Medical Psychology, in Germany. "It almost looks as if people on a Friday evening fly from Paris to New York, and on Monday morning they fly back again."

Okay, but it's fuuuuuuun to fly to New York for the weekend! And yes, I think it goes without saying that we would all be a lot thinner if we had no social lives.

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Researchers speculate that "social jet lag" forces us to eat at odd times, when our bodies aren't prepped for digestion, which could affect the way that we pack on fat. It could also cause "metabolism disruptions at the cellular level." The theories are similar to those that suggest sleep deprivation could contribute to obesity. So, just to sum up, lack of sleep makes you fat, and catching up on sleep also makes you fat. Moral of the story: you're fat.

Whether irregular sleep patterns actively make people gain weight, or the type of people with regimented sleeping habits also tend to be the type with regimented calorie-counting habits, one fact is perfectly clear: I'M TIRED. And I'd like to thank the Germans for this impassioned argument as to why I should go take a nap right now:

Paying more attention to our body clocks may be good for the economy as well as our health, Roennenberg suggests. Rather than bending early birds and night owls to the same work schedule, why not encourage personalized schedules based on each individual's circadian rhythms?

The result would be a better-rested, healthier, and doubtless more productive workforce, Roennenberg says.